Point 2 is wrong. Daimons were not known to be immensely powerful. Back when those regions were not the Zuma Coalition, but rather just "Zuma" (and even the early days of the Zuma Coalition), the daimons usually only fielded armies of 2000 or 3000 CS per unit. One or two Zuma regions actually went rogue a few times, and the daimons lost some battles to rogues. And, even then, after the grew so powerful, the Zuma Coalition was very benign for a long time.
Furthermore, western colonization happened before we knew about the Zuma. Melodia predates general knowledge of the Zuma. Terran's encounters, to my knowledge, are when the Zuma began to get more publicity.
I'm not talking about just Zuma, I'm talking about Daimons as a whole. They'd kicked ass all over BT at the time, so we knew what they were capable of.
And I'm pretty sure that the presence of the Zuma was revealed fairly early on... A few months after Dwilight opened, a long time before Terran existed.
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